A polycarbonate resin is a material which has relatively higher heat resistance than other polymer materials. Due to growing demand for materials having a higher function and higher performance, attempts have been made to provide characteristic features by mixing additives such as a release agent and an ultraviolet absorber into the polycarbonate resin. However, when these additives are mixed, the material tends to deteriorate in heat resistance. For instance, a release agent is often mixed into a resin composition to improve the releasability from a metal mold of a resin molded product at the time of melt molding. When this release agent is added in an effective amount, there is a case where the polycarbonate resin is colored due to the decomposition of the release agent itself at the time of thermal molding or the deterioration of the polycarbonate resin induced by the decomposed product of the release agent.
A large number of proposals have been made to improve the heat resistance of the polycarbonate resin. Most of them are directed to a method in which a phosphorus-based, sulfur-based or hindered phenol-based heat stabilizer is mixed into a polycarbonate resin (refer to patent documents 1 and 2). Although the method in which the heat stabilizer is mixed is effective in improving the heat resistance of the polycarbonate resin, even when the stabilizer is added, satisfactory heat resistance may not be obtained. When a large amount of the heat stabilizer is used, it may reduce the mechanical properties and hydrolytic resistance of the polycarbonate resin.    (patent document 1) JP-A 2001-081302    (patent document 2) JP-A 2001-192544